Improvement in rolls for rolling hoop-iron



NIITED STATES' PATENT @Erica BERNARD LAUTH, 0E HOWARD, PENNSYLVANIA.

IMPROVEMENT IN ROLLS FOR ROLLING HOOP-IRON..

Specification forming part of Letters Patent No. l 72,457, dated January 18, 1876; application led December 18, 1875.

To all whom it may concern:

Be it known that I, BERNARD LAUTE, of Howard, county of Centre, State of Pennsylvania, have invented or discovered a new and useful Improvement in Hoop-Rolling Mill; and I do hereby declare the following to be a full, clear, concise, and exact description thereof, reference being had to the accompanying drawing making apart of this specification, in whichlike letters indicating like parts- Figure lis a side elevation illustrative of my improvement.

My present invention relates to an improvement in the three-high-roll mill patented to me January 19, 186i, No. 41,307, by means of which such mill is adapted to the rolling of hoop and other narrow strips of iron.

The three-high rolls, as used prior to the present improvement, were driven by power applied to the lowest roll, the usual couplingconnection being made only with the neck of such roll. I have found that in using such rolls so coupled up there is a tendency in the middle roll to work endwise, so that in rolling hoop-iron the bearings or housings will frequently be broken by such endwise pressure. This difculty is not experienced in rolll ing broad sheets, and I can only account for the difference in result by the fact that in rolling broad sheets the frictional contact is so great as to overcome such endwise tendency; Whereas, in rolling hoop-iron, the resistance to endwise motion caused by the bite is so small that the difficulty manifests itself with injurious results. I can account for this endwise tendencyof the middle roll only on the theory that it is practically impossibleto bring the axial lines of three such rolls mathematically in the same plane, and, as the two upper rolls, when coupled as described, run by frictional contact alone, any divergence of the axial line of the middle roll from such plane Will result in one end being' driven with more power than the other, which latter Will result in the end- Wise tendency referred to 5 also, the entering of a hoop or other narrow sheet on either side of the middle point of the rolls will increase the same tendency. But whatever' may be the cause of such endwise tendency it frequently results, when the coupling-connection is made with the lower roll, as is usually the case, and

b the usual )ressure-screws D ore uivalent weights. As shown inthe drawing, each of these rolls may have the usual coupling-neck a b c, for convenience in changing the connection with the drivingpower When changing from hoop to sheet, or vice versa; but for the purposes of my present improvement I couple the drivingshaft P, by any suitable fbrm of coupling, p, to the coupling-neck b of the middle roll B. The lower roll is firmly supported in its bearings. The upper roll is held in place by the pressure-screws,in the usual way, and the strain on the middle roll, or the gripe of the coupling thereon, operates in such way as practically to prevent the lateral motion referred to to any such extent as to act injuriously on the machinery or on the product.

Such has been the result of practical experiment, and, as a consequence of this irnprovement, the three-high rolls are adapted to the rolling of hoops, as well as sheets and plates, not limiting myself, however, to hoop-iron, but including, also, other metals and mixtures of metals as to which a narrow, thin product is desired.

The operation described is intended chieliy for linishing and planishing the hoop, which has hitherto been done usually in a two-high mill; but I have found that with a small roll, smaller than can be safely used in a two-high mill for this purpose, I can produce a better article. For some reason or other a small roll will spread the hoop less than a large one; and as spreading is one cause of ragged edges the lessening of this tendency is a material matter; also, a small roll,` perhaps from having a shorter bite in the direction of the feed, will give a smoother and better finish to the product.`

Another advantage in coupling to the middle roll is this: that when the coupling is y made with the lowest roll only, the two upper rolls run by friction alone, and in `rollin g narrow iron the frictional contact is often not sufficient to eect their rotation, particularly when the enclwise tendency of the middle roll manifests itself, as above stated; but by coupling to the middle roll there is but one roll above and one below to be run by friction, and the endwise tendency being obviated, as above described, no difficulty on this account is experienced.

I claim herein as my invention- In a three-high rolling-mill, the upper and' lower rolls A C, in combination with an intermediate roll, B, of less diameter, through which intermediate roll the driving-power is communicated by a couplingconnection from the driving-shaft, substantially as set forth.

In testimony whereof I have hereunto setl my hand..

BERNARD y LAUTH.

Witnesses:

A. H. PEAcocK, J oHN N. LAUTH. 

